Geodynamic reconstructions of the Australides-2: Mesozoic-Cainozoic

The present work, derived from a full global geodynamic reconstruction model over 600 Ma and based on a large database, focuses herein on the interaction between the Pacific, Australian and Antarctic plates since 200 Ma, and proposes integrated solutions for a coherent, physically consistent scenario. The evolution of the Australia-Antarctica-West Pacific plate system is dependent on the Gondwana fit chosen for the reconstruction. Our fit, as defined for the latest Triassic, implies an original scenario for the evolution of the region, in particular for the "early" opening history of the Tasman Sea. The interaction with the Pacific, moreover, is characterised by many magmatic arc migrations and ocean openings, which are stopped by arc-arc collision, arc-spreading axis collision, or arc-oceanic plateau collision, and subduction reversals. Mid-Pacific oceanic plateaus created in the model are much wider than they are on present-day maps, and although they were subducted to a large extent, they were able to stop subduction. We also suggest that adduction processes (i.e., re-emergence of subducted material) may have played an important role, in particular along the plate limit now represented by the Alpine Fault in New Zealand.

Touching the void: exploring virtual objects through a vibrotactile glove

This paper describes a simple low-cost approach toadding an element of haptic interaction within a virtualenvironment. Using off-the-shelf hardware and software wedescribe a simple setup that can be used to explore physically virtual objects in space. This setup comprises of a prototype glove with a number of vibrating actuators to provide the haptic feedback, a Kinect camera for the tracking of the user's hand and a virtual reality development environment. As proof of concept and to test the efficiency of the system as well as its potential applications, we developed a simple application where we created 4 different shapes within a virtual environment in order to try toexplore them and guess their shape through touch alone.

European climate variations over the past half-millennium reconstructed from groundwater

Temperature reconstructions for recent centuries are the basis of estimations of the natural variability in the climate system before and during the onset of anthropogenic perturbation. Here we present, for the first time, an independent and physically based reconstruction of mean annual temperature over the past half millennium obtained from groundwater in France. The reconstructed noble gas temperature (NGT) record suggests cooler than present climate conditions throughout the 16th-19th centuries. Periods of warming occur in the 17th-18th and 20th century, while cooling is reconstructed in the 19th century. A noticeable coincidence with other temperature records is demonstrated. Deuterium excess varies in parallel with the NGT, and indicates variation in the seasonality of the aquifer recharge; whereas high excess air in groundwater indicates periods with high oscillations of the water table.

Responses to a crisis: FASA-Renault in Spain during the 1970s

[cat] Aquest treball analitza la trajectòria de l’empresa FASA-Renault durant la dècada dels setanta del segle XX. Aquest període compren els primers anys de la crisis experimentada per l’economia i la industria espanyola entre 1974 y 1985. A nivell extern, l’economia espanyola es va veure afectada per dos xocs en el preu del petroli. A nivell intern, la industria de l’automòbil es va veure afectat per un decret governamental: es tractava de l’anomenat decret “Ford”, aprovat l’any 1972, el qual facilitava l’establiment de Ford a Espanya. Aquest decret va tenir greus conseqüències per a SEAT, el principal productor espanyol. Entre 1972 y 1980 la producció de SEAT es va reduir en una tercera part i la seva situació financera va esdevenir insostenible. Per contra, en aquest període FASA-Renault va esdevenir el principal productor ubicat a Espanya (la seva producció es va multiplicar per 3,5 durant els anys setanta) i en líder de ventes en el mercat espanyol (la seva penetració es va incrementar del 23 al 36%). El principal objectiu del treball es analitzar els factor que expliquen l’èxit de FASARenault durant els anys setanta.

Responses to a crisis: FASA-Renault in Spain during the 1970s

[cat] Aquest treball analitza la trajectòria de l’empresa FASA-Renault durant la dècada dels setanta del segle XX. Aquest període compren els primers anys de la crisis experimentada per l’economia i la industria espanyola entre 1974 y 1985. A nivell extern, l’economia espanyola es va veure afectada per dos xocs en el preu del petroli. A nivell intern, la industria de l’automòbil es va veure afectat per un decret governamental: es tractava de l’anomenat decret “Ford”, aprovat l’any 1972, el qual facilitava l’establiment de Ford a Espanya. Aquest decret va tenir greus conseqüències per a SEAT, el principal productor espanyol. Entre 1972 y 1980 la producció de SEAT es va reduir en una tercera part i la seva situació financera va esdevenir insostenible. Per contra, en aquest període FASA-Renault va esdevenir el principal productor ubicat a Espanya (la seva producció es va multiplicar per 3,5 durant els anys setanta) i en líder de ventes en el mercat espanyol (la seva penetració es va incrementar del 23 al 36%). El principal objectiu del treball es analitzar els factor que expliquen l’èxit de FASARenault durant els anys setanta.

Effects of the 80 km/h and variable speed limits on air pollution in the metropolitan area of Barcelona

In 2008 the regional government of Catalonia (Spain) reduced the maximum speed limit on several stretches of congested urban motorway in the Barcelona metropolitan area to 80 km/h, while in 2009 it introduced a variable speed system on other stretches of its metropolitan motorways. We use the differences-in-differences method, which enables a policy impact to be measured under specific conditions, to assess the impact of these policies on emissions of NOx and PM10. Empirical estimation indicate that reducing the speed limit to 80 km h-1 causes a 1.7 to 3.2% increase in NOx and 5.3 to 5.9% in PM10. By contrast, the variable speed policy reduced NOx and PM10 pollution by 7.7 to 17.1% and 14.5 to 17.3%. As such, a variable speed policy appears to be a more effective environmental policy than reducing the speed limit to a maximum of 80 km/h.

Association of car ownership and physical activity across the spectrum of human development : Modeling the Epidemiologic Transition Study (METS).

BACKGROUND: Variations in physical activity (PA) across nations may be driven by socioeconomic position. As national incomes increase, car ownership becomes within reach of more individuals. This report characterizes associations between car ownership and PA in African-origin populations across 5 sites at different levels of economic development and with different transportation infrastructures: US, Seychelles, Jamaica, South Africa, and Ghana. METHODS: Twenty-five hundred adults, ages 25-45, were enrolled in the study. A total of 2,101 subjects had valid accelerometer-based PA measures (reported as average daily duration of moderate to vigorous PA, MVPA) and complete socioeconomic information. Our primary exposure of interest was whether the household owned a car. We adjusted for socioeconomic position using household income and ownership of common goods. RESULTS: Overall, PA levels did not vary largely between sites, with highest levels in South Africa, lowest in the US. Across all sites, greater PA was consistently associated with male gender, fewer years of education, manual occupations, lower income, and owning fewer material goods. We found heterogeneity across sites in car ownership: after adjustment for confounders, car owners in the US had 24.3 fewer minutes of MVPA compared to non-car owners in the US (20.7 vs. 45.1 minutes/day of MVPA); in the non-US sites, car-owners had an average of 9.7 fewer minutes of MVPA than non-car owners (24.9 vs. 34.6 minutes/day of MVPA). CONCLUSIONS: PA levels are similar across all study sites except Jamaica, despite very different levels of socioeconomic development. Not owning a car in the US is associated with especially high levels of MVPA. As car ownership becomes prevalent in the developing world, strategies to promote alternative forms of active transit may become important.

Bone Mineral Accrual in Physically Active Girls. With Special Reference to Reduction in Physical Activity Level and Use of Oral Contraceptives

Adolescence is an important time for acquiring high peak bone mass. Physical activity is known to be beneficial to bone development. The effect of estrogen-progestin contraceptives (EPC) is still controversial. Altogether 142 (52 gymnasts, 46 runners, and 42 controls) adolescent women participated in this study, which is based on two 7-year (n =142), one 6-year (n =140) and one 4-year (n =122) follow-ups. Information on physical activity, menstrual history, sexual maturation, nutrition, living habits and health status was obtained through questionnaires and interviews. The bone mineral density (BMD) and content (BMC) of lumbar spine (LS) and femoral neck (FN) were measured by dual- energy X-ray absoptiometry. Calcaneal sonographic measurements were also made. The physical activity of the athletes participating in this study decreased after 3-year follow-up. High-impact exercise was beneficial to bones. LS and FN BMC was higher in gymnasts than in controls during the follow-up. Reduction in physical activity had negative effects on bone mass. LS and FN BMC increased less in the group having reduced their physical activity more than 50%, compared with those continuing at the previous level (1.69 g, p=0.021; 0.14 g, p=0.015, respectively). The amount of physical activity was the only significant parameter accounting for the calcaneal sonography measurements at 6-year follow-up (11.3%) and reduced activity level was associated with lower sonographic values. Long-term low-dose EPC use seemed to prevent normal bone mass acquisition. There was a significant trend towards a smaller increase in LS and FN BMC among long-term EPC users. In conclusion, this study confirms that high-impact exercise is beneficial to bones and that the benefits are partly maintained even after a clear reduction in training level at least for 4 years. Continued exercise is needed to retain all acquired benefits. The bone mass gained and maintained can possibly be maximized in adolescence by implementing high-impact exercise for youngsters. The peak bone mass of the young women participating in the study may be reached before the age of 20. Use of low-dose EPCs seems to suppress normal bone mass acquisition.

Regional differences of physical activity and sedentary behaviour in Swiss children are not explained by socio-demographics or the built environment.

OBJECTIVE: We evaluated whether regional differences in physical activity (PA) and sedentary behaviour (SB) existed along language boundaries within Switzerland and whether potential differences would be explained by socio-demographics or environmental characteristics. METHODS: We combined data of 611 children aged 4 to 7 years from four regional studies. PA and SB were assessed by accelerometers. Information about the socio-demographic background was obtained by questionnaires. Objective neighbourhood attributes could be linked to home addresses. Multivariate regression models were used to test associations between PA and SB and socio-demographic characteristics and neighbourhood attributes. RESULTS: Children from the German compared to the French-speaking region were more physically active and less sedentary (by 10-15 %, p < 0.01). Although German-speaking children lived in a more favourable environment and a higher socioeconomic neighbourhood (differences p < 0.001), these characteristics did not explain the differences in PA behaviour between French and German speaking. CONCLUSIONS: Factors related to the language region, which might be culturally rooted were among the strongest correlates of PA and SB among Swiss children, independent of individual, social and environmental factors.

Accounting research: a critical view of the present situation and prospects

In this study we critically review the internal procedures of the accounting community for generating and disseminating knowledge. We contend that academic journals on accounting research are scarce, publish few articles and apply high rejection rates, and the review process is lengthy and expensive. Additionally, an academic elite has unparalleled predominance in comparison to other business disciplines, reflected in an unusual share of published articles with authors affiliated to a small number of academic institutions, and the predominance of certain topics and methodologies. The discipline does not allow the collaborative, iterative and flexible features of innovative knowledge communities. The discipline¿s internal procedures favour restriction, control, slowness, and expiration, rather than participation, speed and renewal. They are ill suited for advancing knowledge and bode badly for successful research. As a result, accounting academics present low research performance and the discipline is facing steady decline. More importantly, the discipline is handicapped in producing innovative knowledge able to contribute to critical research and long term social well-being. We also focus on the Spanish institutional situation, arguing that Spanish requirements for reaching tenured positions are difficult for accountants to meet. We highlight the need to raise awareness of the problem and change the procedures.

Paranoia and post-traumatic stress disorder in the months after a physical assault: a longitudinal study examining shared and differential predictors.

Background: Being physically assaulted is known to increase the risk of the occurrence of post-traumatic stress disorder (PTSD) symptoms but it may also skew judgements about the intentions of other people. The objectives of the study were to assess paranoia and PTSD after an assault and to test whether theory-derived cognitive factors predicted the persistence of these problems. Method: At 4 weeks after hospital attendance due to an assault, 106 people were assessed on multiple symptom measures (including virtual reality) and cognitive factors from models of paranoia and PTSD. The symptom measures were repeated 3 and 6 months later. Results: Factor analysis indicated that paranoia and PTSD were distinct experiences, though positively correlated. At 4 weeks, 33% of participants met diagnostic criteria for PTSD, falling to 16% at follow-up. Of the group at the first assessment, 80% reported that since the assault they were excessively fearful of other people, which over time fell to 66%. Almost all the cognitive factors (including information-processing style during the trauma, mental defeat, qualities of unwanted memories, self-blame, negative thoughts about self, worry, safety behaviours, anomalous internal experiences and cognitive inflexibility) predicted later paranoia and PTSD, but there was little evidence of differential prediction. Conclusions: Paranoia after an assault may be common and distinguishable from PTSD but predicted by a strikingly similar range of factors.

The role of endothelial enzymes NOS, VAP-1 and CD73 in acute lung injury

Acute lung injury (ALI) is a syndrome of acute hypoxemic respiratory failure with bilateral pulmonary infiltrates that is not caused by left atrial hypertension. Since there is no effective treatment available, this frequent clinical syndrome significantly contributes to mortality of both medical and surgical patients. Great majority of the patients with the syndrome suffers from indirect ALI caused by systemic inflammatory response syndrome (SIRS). Sepsis, trauma, major surgery and severe burns, which represent the most common triggers of SIRS, often induce an overwhelming inflammatory reaction leading to dysfunction of several vital organs. Studies of indirect ALI due to SIRS revealed that respiratory dysfunction results from increased permeability of endothelium. Disruption of endothelial barrier allows extravasation of protein-rich liquid and neutrophils to pulmonary parenchyma. Both under normal conditions and in inflammation, endothelial barrier function is regulated by numerous mechanisms. Endothelial enzymes represent one of the critical control points of vascular permeability and leukocyte trafficking. Some endothelial enzymes prevent disruption of endothelial barrier by production of anti-inflammatory substances. For instance, nitric oxide synthase (NOS) down-regulates leukocyte extravasation in inflammation by generation of nitric oxide. CD73 decreases vascular leakage and neutrophil emigration to inflamed tissues by generation of adenosine. On the other hand, vascular adhesion protein-1 (VAP-1) mediates leukocyte trafficking to the sites of inflammation both by generation of pro-inflammatory substances and by physically acting as an adhesion molecule. The aims of this study were to define the role of endothelial enzymes NOS, CD73 and VAP-1 in acute lung injury. Our data suggest that increasing substrate availability for NOS reduces both lung edema and neutrophil infiltration and this effect is not enhanced by concomitant administration of antioxidants. CD73 protects from vascular leakage in ALI and its up-regulation by interferon-β represents a novel therapeutic strategy for treatment of this syndrome. Enzymatic activity of VAP-1 mediates neutrophil infiltration in ALI and its inhibition represents an attractive approach to treat ALI.

Mitotic regulation by Polo-like kinase 1 and the Chromosomal Passenger Complex

During mitosis, the duplicated genome must be accurately divided between two daughter cells. Polo-like kinase 1 (Plk1) and Aurora B kinase, together with its binding partners Incenp, Survivin and Borealin (chromosomal passenger complex, CPC), have key roles in coordinating mitotic events. The accuracy of cell division is safeguarded by a signaling cascade termed the mitotic spindle checkpoint (SC), which ensures that chromosomes are not physically separated before correct bipolar attachments have been formed between kinetochores and spindle microtubules (MT). An inhibitory “wait anaphase” signal, which delays chromosome separation (anaphase onset), is created at individual kinetochores and broadcasted throughout the cell in response to lack of kinetochore-microtubule (kMT) attachment or proper interkinetochore tension. It is believed that the fast turnover of SC molecules at kinetochores contributes to the cell’s ability to produce this signal and enables rapid responses to changing cellular conditions. Kinetochores that lack MT attachment and tension express a certain phosphoepitope called the 3F3/2 phosphoepitope, which has been linked to SC signaling. In the experimental part, we investigated the regulation of the 3F3/2 phosphoepitope, analyzed whether CPC molecules turn over at centromeres, and dissected the mitotic roles of the CPC using a microinjection technique that allowed precise temporal control over its function. We found that the kinetochore 3F3/2 phosphoepitope is created by Plk1, and that CPC proteins exhibit constant exchange at centromeres. Moreover, we found that CPC function is necessary in the regulation of chromatid movements and spindle morphology in anaphase. In summary, we identified new functions of key mitotic regulators Plk1 and CPC, and provided insighs into the coordination of mitotic events.

A Practical Micro Mechanical Model Based Local Approach Methodology for the Analysis of Ductile Fracture of Welded T-Joints

This thesis concentrates on developing a practical local approach methodology based on micro mechanical models for the analysis of ductile fracture of welded joints. Two major problems involved in the local approach, namely the dilational constitutive relation reflecting the softening behaviour of material, and the failure criterion associated with the constitutive equation, have been studied in detail. Firstly, considerable efforts were made on the numerical integration and computer implementation for the non trivial dilational Gurson Tvergaard model. Considering the weaknesses of the widely used Euler forward integration algorithms, a family of generalized mid point algorithms is proposed for the Gurson Tvergaard model. Correspondingly, based on the decomposition of stresses into hydrostatic and deviatoric parts, an explicit seven parameter expression for the consistent tangent moduli of the algorithms is presented. This explicit formula avoids any matrix inversion during numerical iteration and thus greatly facilitates the computer implementation of the algorithms and increase the efficiency of the code. The accuracy of the proposed algorithms and other conventional algorithms has been assessed in a systematic manner in order to highlight the best algorithm for this study. The accurate and efficient performance of present finite element implementation of the proposed algorithms has been demonstrated by various numerical examples. It has been found that the true mid point algorithm (a = 0.5) is the most accurate one when the deviatoric strain increment is radial to the yield surface and it is very important to use the consistent tangent moduli in the Newton iteration procedure. Secondly, an assessment of the consistency of current local failure criteria for ductile fracture, the critical void growth criterion, the constant critical void volume fraction criterion and Thomason's plastic limit load failure criterion, has been made. Significant differences in the predictions of ductility by the three criteria were found. By assuming the void grows spherically and using the void volume fraction from the Gurson Tvergaard model to calculate the current void matrix geometry, Thomason's failure criterion has been modified and a new failure criterion for the Gurson Tvergaard model is presented. Comparison with Koplik and Needleman's finite element results shows that the new failure criterion is fairly accurate indeed. A novel feature of the new failure criterion is that a mechanism for void coalescence is incorporated into the constitutive model. Hence the material failure is a natural result of the development of macroscopic plastic flow and the microscopic internal necking mechanism. By the new failure criterion, the critical void volume fraction is not a material constant and the initial void volume fraction and/or void nucleation parameters essentially control the material failure. This feature is very desirable and makes the numerical calibration of void nucleation parameters(s) possible and physically sound. Thirdly, a local approach methodology based on the above two major contributions has been built up in ABAQUS via the user material subroutine UMAT and applied to welded T joints. By using the void nucleation parameters calibrated from simple smooth and notched specimens, it was found that the fracture behaviour of the welded T joints can be well predicted using present methodology. This application has shown how the damage parameters of both base material and heat affected zone (HAZ) material can be obtained in a step by step manner and how useful and capable the local approach methodology is in the analysis of fracture behaviour and crack development as well as structural integrity assessment of practical problems where non homogeneous materials are involved. Finally, a procedure for the possible engineering application of the present methodology is suggested and discussed.

On the Application of Beam on Elastic Foundation Theory to the Analysis of Stiffened Plate Strips

The main objective of this thesis is to show that plate strips subjected to transverse line loads can be analysed by using the beam on elastic foundation (BEF) approach. It is shown that the elastic behaviour of both the centre line section of a semi infinite plate supported along two edges, and the free edge of a cantilever plate strip can be accurately predicted by calculations based on the two parameter BEF theory. The transverse bending stiffness of the plate strip forms the foundation. The foundation modulus is shown, mathematically and physically, to be the zero order term of the fourth order differential equation governing the behaviour of BEF, whereas the torsion rigidity of the plate acts like pre tension in the second order term. Direct equivalence is obtained for harmonic line loading by comparing the differential equations of Levy's method (a simply supported plate) with the BEF method. By equating the second and zero order terms of the semi infinite BEF model for each harmonic component, two parameters are obtained for a simply supported plate of width B: the characteristic length, 1/ λ, and the normalized sum, n, being the effect of axial loading and stiffening resulting from the torsion stiffness, nlin. This procedure gives the following result for the first mode when a uniaxial stress field was assumed (ν = 0): 1/λ = √2B/π and nlin = 1. For constant line loading, which is the superimposition of harmonic components, slightly differing foundation parameters are obtained when the maximum deflection and bending moment values of the theoretical plate, with v = 0, and BEF analysis solutions are equated: 1 /λ= 1.47B/π and nlin. = 0.59 for a simply supported plate; and 1/λ = 0.99B/π and nlin = 0.25 for a fixed plate. The BEF parameters of the plate strip with a free edge are determined based solely on finite element analysis (FEA) results: 1/λ = 1.29B/π and nlin. = 0.65, where B is the double width of the cantilever plate strip. The stress biaxial, v > 0, is shown not to affect the values of the BEF parameters significantly the result of the geometric nonlinearity caused by in plane, axial and biaxial loading is studied theoretically by comparing the differential equations of Levy's method with the BEF approach. The BEF model is generalised to take into account the elastic rotation stiffness of the longitudinal edges. Finally, formulae are presented that take into account the effect of Poisson's ratio, and geometric non linearity, on bending behaviour resulting from axial and transverse inplane loading. It is also shown that the BEF parameters of the semi infinite model are valid for linear elastic analysis of a plate strip of finite length. The BEF model was verified by applying it to the analysis of bending stresses caused by misalignments in a laboratory test panel. In summary, it can be concluded that the advantages of the BEF theory are that it is a simple tool, and that it is accurate enough for specific stress analysis of semi infinite and finite plate bending problems.